Oscillator, electronic device, and vehicle

ABSTRACT

An oscillator includes a first container that includes a first base substrate and a first lid and that has a first internal space, a second container that is fixed to the first base substrate in the first internal space and that includes a second base substrate and a second lid and that has a second internal space, a resonator element that is disposed on the lower surface side of the second base substrate in the second internal space, a temperature sensor that is disposed on the upper surface side of the second base substrate, a first circuit element that includes an oscillation circuit and a second circuit element that is fixed to the first base substrate in the first internal space and that includes a frequency control circuit that controls a frequency of the oscillation signal output by the oscillation circuit. The second container and the second circuit element are arranged side by side in plan view.

The present application is based on, and claims priority from JPApplication Serial Number 2019-031052, filed Feb. 22, 2019, thedisclosure of which is hereby incorporated by reference herein in itsentirety.

BACKGROUND 1. Technical Field

The present disclosure relates to an oscillator, an electronic device,and a vehicle.

2. Related Art

JP-A-2014-107862 discloses an oscillator including an outer package, aninner package accommodated in the outer package, a resonator elementaccommodated in the inner package, and circuit elements accommodated inthe outer package and arranged side by side with the inner package inplan view. In the oscillator of JP-A-2014-107862, the circuit elementincludes a temperature sensor, and the frequency of an output signal iscorrected based on the temperature detected by the temperature sensor.

However, in the oscillator of JP-A-2014-107862, since the circuitelement including the temperature sensor is located outside the innerpackage that accommodates the resonator element, a temperaturedifference between the temperature sensor and the resonator element islikely to occur, and it is difficult to correct the output signal withhigh accuracy. As a result, the frequency accuracy of the output signalmay be reduced.

SUMMARY

An oscillator according to an aspect of the present disclosure includesa first container that includes a first base substrate and a first lidbonded to the first base substrate and that has a first internal space,a second container that is fixed to the first base substrate in thefirst internal space and that includes a second base substrate and asecond lid bonded to one main surface side of the second base substrateand has a second internal space, a resonator element that is disposed onthe one main surface side of the second base substrate in the secondinternal space, a temperature sensor that is disposed on the other mainsurface side of the second base substrate, a first circuit element thatis disposed on the other main surface side of the second base substrateand that includes an oscillation circuit oscillating the resonatorelement and generating an oscillation signal on which temperaturecompensation is performed based on a detected temperature of thetemperature sensor, and a second circuit element that is fixed to thefirst base substrate in the first internal space and includes afrequency control circuit that controls a frequency of the oscillationsignal, in which the second container and the second circuit element arearranged side by side in plan view.

In the oscillator according to the application example of thedisclosure, the second base substrate may include a first recess portionthat opens on the one main surface and a second recess portion thatopens on the other main surface, the resonator element may be disposedat a bottom of the first recess portion, and the first circuit elementmay be disposed at a bottom of the second recess portion.

In the oscillator according to the application example of thedisclosure, the temperature sensor may be integrated with the firstcircuit element.

In the oscillator according to the application example of thedisclosure, the first base substrate may include a first portion and asecond portion thicker than the first portion, the second container maybe fixed to one of the first portion and the second portion, and thesecond circuit element may be fixed to the other thereof.

In the oscillator according to the application example of thedisclosure, a thinner one of the second container and the second circuitelement may be fixed to the second portion, and a thicker one may befixed to the first portion.

In the oscillator according to the application example of thedisclosure, the second container may include a temperature outputterminal from which an output signal of the temperature sensor isoutput, and the temperature output terminal may be electrically coupledto the frequency control circuit.

In the oscillator according to the application example of thedisclosure, the second container may include a power supply terminal towhich a power supply voltage supplied to the oscillation circuit isapplied, and the oscillator may further include a bypass capacitor thatis accommodated in the first container, and is coupled to the powersupply terminal.

The oscillator according to the application example of the disclosuremay further include a first bypass capacitor and a second bypasscapacitor that are accommodated in the first container and are fixed tothe first base substrate, in which one end of the first bypass capacitorand one end of the second bypass capacitor may be disposed to face eachother, and end portions on facing sides of the first bypass capacitorand the second bypass capacitor may have the same potential.

In the oscillator according to the application example of thedisclosure, the second container may be fixed to the first basesubstrate via an insulating bonding member.

In the oscillator according to the application example of thedisclosure, the second container may include a first side and a secondside closer to the second circuit element than the first side in planview, and an oscillation output terminal from which the oscillationsignal is output, and the oscillation output terminal may be provided atone of two corners located at both ends of the second side.

In the oscillator according to the application example of thedisclosure, the second lid of the second container may be fixed to thefirst base substrate.

An electronic device according to an application example of thedisclosure includes the oscillator described above and a signalprocessing circuit that performs signal processing based on an outputsignal of the oscillator.

A vehicle according to an application example of the disclosure includesthe oscillator described above and a signal processing circuit thatperforms signal processing based on an output signal of the oscillator.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional view showing an oscillator according to afirst embodiment.

FIG. 2 is a plan view showing the oscillator of FIG. 1.

FIG. 3 is a cross-sectional view taken along line III-III in FIG. 2.

FIG. 4 is a plan view of a temperature compensated crystal oscillatorincluded in the oscillator of FIG. 1 as viewed from below.

FIG. 5 is a circuit view of a second circuit element included in theoscillator of FIG. 1.

FIG. 6 is a cross-sectional view showing an oscillator according to asecond embodiment.

FIG. 7 is a perspective view showing a personal computer according to athird embodiment.

FIG. 8 is a perspective view showing an automobile according to a fourthembodiment.

DESCRIPTION OF EXEMPLARY EMBODIMENTS

Hereinafter, preferred embodiments of an oscillator, an electronicdevice, and a vehicle according to the disclosure will be described indetail with reference to the accompanying drawings.

First Embodiment

FIG. 1 is a cross-sectional view showing an oscillator according to afirst embodiment. FIG. 2 is a plan view showing the oscillator ofFIG. 1. FIG. 3 is a cross-sectional view taken along line III-III inFIG. 2. FIG. 4 is a plan view of a temperature compensated crystaloscillator included in the oscillator of FIG. 1 as viewed from below.FIG. 5 is a circuit view of a second circuit element included in theoscillator of FIG. 1. For convenience of description, each figure showsan X axis, a Y axis, and a Z axis that are orthogonal to each other. Inthe following, the arrow tip side of each axis is referred to as “plus”,and the opposite side is referred to as “minus”. The Z-axis directionplus side is also referred to as “upper”, and the Z-axis direction minusside is also referred to as “lower”. The plan view from the Z-axisdirection is also simply referred to as “plan view”.

The oscillator 1 shown in FIGS. 1 and 2 includes an outer package 2, atemperature compensated crystal oscillator 3 (TCXO) accommodated in theouter package 2, a second circuit element 4, and discrete components 81and 82. The temperature compensated crystal oscillator 3 includes aninner package 5, a resonator element 6 and a first circuit element 7accommodated in the inner package 5.

The outer package 2 includes a first base substrate 21 having a recessportion 211 that opens on the upper surface, and a first lid 22 that isbonded to the upper surface of the first base substrate 21 via a bondingmember 23 so as to close the opening of the recess portion 211. Anairtight first internal space S2 is formed inside the outer package 2 bythe recess portion 211, and the temperature compensated crystaloscillator 3, the first circuit element 7, and the discrete components81 and 82 are housed in the first internal space S2. Although notparticularly limited, the first base substrate 21 can be made ofceramics such as alumina, and the first lid 22 can be made of a metalmaterial such as Kovar.

The recess portion 211 is constituted by a plurality of recess portions.In the configuration shown in the drawing, the recess portion 211includes a recess portion 211 a that opens on the upper surface of thefirst base substrate 21, and a recess portion 211 b and a recess portion211 c that open on the bottom surface of the recess portion 211 a andhave a smaller opening than the recess portion 211 a. The recessportions 211 b and 211 c are formed side by side in the X-axisdirection, and a depth Db of the recess portion 211 b is greater than adepth Dc of the recess portion 211 c. Therefore, the bottom surface ofthe recess portion 211 b is located below the bottom surface of therecess portion 211 c. Further, a thickness tb of the portion of thefirst base substrate 21 that overlaps the recess portion 211 b issmaller than a thickness tc of the portion that overlaps the recessportion 211 c. Hereinafter, the portion of the first base substrate 21overlapping the recess portion 211 b is also referred to as “thinportion 21A”, and the portion of the first base substrate 21 overlappingthe recess portion 211 c is also referred to as “thick portion 21B”.However, the configuration of the recess portion 211 is not particularlylimited.

The second circuit element 4 is fixed to the bottom surface of therecess portion 211 c, and the temperature compensated crystal oscillator3 is fixed to the bottom surface of the recess portion 211 b. As shownin FIG. 2, two discrete components 81 and 82, which are single circuitcomponents, are fixed to the bottom surface of the recess portion 211 bso as not to overlap the temperature compensated crystal oscillator 3.According to such an arrangement, the second circuit element 4, thetemperature compensated crystal oscillator 3, and each discretecomponent 81 and 82 can be arranged in the X-axis direction and theY-axis direction without overlapping in the Z-axis direction in planview. Therefore, the height of the outer package 2 can be reduced.

Further, as shown in FIG. 1, a plurality of internal terminals 241 arearranged on the bottom surface of the recess portion 211 a, and aplurality of external terminals 243 are arranged on the bottom surfaceof the first base substrate 21. These internal terminals 241 or theinternal terminals 241 and the external terminals 243 are electricallycoupled via a wiring (not shown) formed in the first base substrate 21.Some internal terminals 241 are electrically coupled to the secondcircuit element 4 through bonding wires BW1, and some internal terminals241 are electrically coupled to the temperature compensated crystaloscillator 3 through bonding wires BW2.

The atmosphere of the first internal space S2 is not particularlylimited, but for example, may be a reduced pressure state, particularlya vacuum state, which is replaced with an inert gas such as nitrogen orargon and reduced in pressure relative to the atmospheric pressure.Thereby, the heat-insulating property of the outer package 2 isenhanced, and the oscillator 1 is hardly affected by the externaltemperature. Further, heat exchange between the inner package 5accommodated in the outer package 2 and the second circuit element 4,particularly heat exchange by convection is suppressed. Therefore, it ispossible to prevent a temperature sensor 71 and the resonator element 6included in the first circuit element 7 from being heated unevenly bythe heat of the second circuit element 4. That is, it is possible tosuppress the occurrence of a temperature difference between theresonator element 6 and the temperature sensor 71 due to the heat of thesecond circuit element 4. Therefore, the temperature sensor 71 canaccurately detect the temperature of the resonator element 6, and thehighly accurate oscillator 1 can be obtained.

The atmosphere of the first internal space S2 is not limited thereto,and may be, for example, an atmospheric pressure state or a pressurizedstate. The first internal space S2 may not be replaced with an inert gassuch as nitrogen or argon, but may be filled with atmosphere, that is,air. The first internal space S2 may not be airtight but may communicatewith the outside of the outer package 2.

As shown in FIG. 3, the temperature compensated crystal oscillator 3includes the inner package 5, the resonator element 6 accommodated inthe inner package 5, and the first circuit element 7 disposed outsidethe inner package 5. The inner package 5 includes a second basesubstrate 51 having a first recess portion 511 that opens on the lowersurface and a second recess portion 512 that opens on the upper surface,and a second lid 52 bonded to the lower surface of the second basesubstrate 51 via a bonding member 53 so as to close the opening of thefirst recess portion 511. An airtight second internal space S5 is formedin the inner package 5 by the first recess portion 511, and theresonator element 6 is accommodated in the second internal space S5.Although not particularly limited, the second base substrate 51 can bemade of ceramics such as alumina, and the second lid 52 can be made of ametal material such as Kovar.

The first recess portion 511 is constituted by a plurality of recessportions, and in the present embodiment, includes a recess portion 511 athat opens on the lower surface of the second base substrate 51, and arecess portion 511 b that opens on the bottom surface of the recessportion 511 a and has a smaller opening than the recess 511 a. On theother hand, the second recess portion 512 is constituted by a pluralityof recess portions, and includes a recess portion 512 a that opens onthe upper surface of the second base substrate 51, and a recess portion512 b that opens on the bottom surface of the recess portion 512 a andhas a smaller opening than the recess portion 512 a in the configurationshown in the drawing. However, the configuration of the first and secondrecess portions 511 and 512 is not particularly limited.

The resonator element 6 is fixed to the bottom surface of the recessportion 511 b, and the first circuit element 7 is fixed to the bottomsurface of the recess portion 512 b. According to such an arrangement,the resonator element 6 and the first circuit element 7 can be arrangedso as to overlap in the Z-axis direction, that is, in the heightdirection of the oscillator 1. Therefore, these can be arrangedcompactly in the inner package 5, and the size of the temperaturecompensated crystal oscillator 3 can be reduced. In addition, theresonator element 6 and the first circuit element 7 are disposed with aplate-like portion 513 pinched between the first recess portion 511 andthe second recess portion 512 of the second base substrate 51 interposedtherebetween, and the resonator element 6 and the first circuit element7 are thermally coupled via the portion 513, and the temperaturedifference between the resonator element 6 and the temperature sensor 71in the first circuit element 7 becomes smaller. Therefore, thetemperature sensor 71 can accurately detect the temperature of theresonator element 6. A molding material for molding the first circuitelement 7 may be disposed in the second recess portion 512.

However, the configuration of the second base substrate 51 is notparticularly limited, and for example, the second recess portion 512 maybe omitted. In this case, the first circuit element 7 may be disposed onthe upper surface of the second base substrate 51.

A plurality of internal terminals 541 are disposed on the bottom surfaceof the recess portion 511 a, a plurality of internal terminals 542 aredisposed on the bottom surface of the recess portion 512 a, and aplurality of external terminals 543 are disposed on the upper surface ofthe second base substrate 51. The internal terminals 541 and 542 and theexternal terminal 543 are electrically coupled via a wiring (not shown)formed in the second base substrate 51. Each of the plurality ofinternal terminals 541 is electrically coupled to the resonator element6 via a bonding wire BW3, and each of the plurality of internalterminals 542 is electrically coupled to the first circuit element 7 viaa bonding wire BW4. However, the connection method between the resonatorelement 6 and the internal terminal 541 and the connection methodbetween the first circuit element 7 and the internal terminal 542 arenot particularly limited.

The atmosphere of the second internal space S5 is not particularlylimited, but for example, may be a reduced pressure state, particularlya vacuum state, which is replaced with an inert gas such as nitrogen orargon and reduced in pressure relative to the atmospheric pressure.Thereby, viscous resistance decreases and the resonator element 6 can bevibrated efficiently. However, the atmosphere of the second internalspace S5 is not limited thereto, and may be an atmospheric pressurestate or a pressurized state. Accordingly, heat transfer due toconvection is likely to occur in the second internal space S5, thetemperature difference between the resonator element 6 and thetemperature sensor 71 can be further reduced, and the temperature sensor71 detects the temperature of the resonator element 6 with accuracy. Thesecond internal space S5 may not be replaced with an inert gas such asnitrogen or argon, but may be filled with atmosphere, that is, air.Further, the second internal space S5 is not airtight and maycommunicate with the first internal space S2.

The resonator element 6 is an AT cut quartz crystal resonator element.Since the AT cut quartz crystal resonator element has a third-orderfrequency-temperature characteristics, the resonator element 6 hasexcellent frequency stability. As shown in FIG. 4, the resonator element6 includes a rectangular quartz crystal substrate 60 cut out by AT cut,and an electrode 61 disposed on the surface of the quartz crystalsubstrate 60. The electrode 61 includes a first excitation electrode 621disposed on the lower surface of the quartz crystal substrate 60 and asecond excitation electrode 631 disposed on the upper surface of thequartz crystal substrate 60 and facing a first excitation electrode 621through the quartz crystal substrate 60. In addition, the electrode 61includes a first pad electrode 622 and a second pad electrode 632 whichare arranged on the lower surface of the quartz crystal substrate 60 andaligned with the edge thereof, a first extraction electrode 623 thatelectrically couples the first excitation electrode 621 and the firstpad electrode 622, and a second extraction electrode 633 thatelectrically couples the second excitation electrode 631 and the secondpad electrode 632.

Such a resonator element 6 is bonded to the bottom surface of the recessportion 511 b via a bonding member B3 at one end thereof. The first padelectrode 622 and the second pad electrode 632 are each electricallycoupled with the internal terminal 541 via the bonding wire BW3. Each ofthe first pad electrode 622 and the second pad electrode 632 may beelectrically coupled to the inner package 5 via a conductive adhesiveinstead of via a bonding wire. The bonding member B3 is not particularlylimited, may be, for example, a conductive bonding member typified by ametal bump, solder, a brazing material, a metal paste, and a conductiveresin adhesive, or may be an insulating bonding member typified byvarious resin adhesives such as epoxy, silicone, and polyimide, but maybe a conductive bonding member.

Since the conductive bonding member includes a metal material, theconductive bonding member has a higher thermal conductivity than aninsulating bonding member that does not include a metal materialtypified by a resin adhesive. Therefore, the resonator element 6 and thefirst circuit element 7 are easily thermally coupled via the bondingmember B3 and the second base substrate 51, and the temperaturedifference therebetween can be further reduced. Therefore, thetemperature sensor 71 can accurately detect the temperature of theresonator element 6.

However, the configuration of the resonator element 6 is notparticularly limited. For example, the plan view shape of the quartzcrystal substrate 60 is not limited to a rectangle. As the resonatorelement 6, in addition to the AT-cut quartz crystal resonator element,an SC-cut quartz crystal resonator element, a BT-cut quartz crystalresonator element, a tuning fork type quartz crystal resonator element,a surface acoustic wave resonator, other piezoelectric resonatorelements, and a micro electromechanical system (MEMS) resonator elementcan also be used.

Further, in place of the quartz crystal substrate 60, variouspiezoelectric substrates such as lithium niobate (LiNbO₃), lithiumtantalate (LiTaO₃), lead zirconate titanate (PZT), lithium tetraborate(Li₂B₄O₇), langasite (La₃Ga₅SiO₁₄), potassium niobate (KNbO₃), galliumphosphate (GaPO₄), gallium arsenide (GaAs), aluminum nitride (AlN), zincoxide (ZnO, Zn₂O₃), barium titanate (BaTiO₃), lead titanate (PbPO₃),sodium potassium niobate ((K, Na)NbO₃), bismuth ferrite (BiFeO₃), sodiumniobate (NaNbO₃), bismuth titanate (Bi₄Ti₃O₁₂), bismuth sodium titanate(Na_(0.5)Bi_(0.5)TiO₃), and the like may be used, or for example, asubstrate other than the piezoelectric substrates, such as a siliconsubstrate may also be used.

As shown in FIGS. 1 to 3, the first circuit element 7 includes thetemperature sensor 71 and an oscillation circuit 72. The oscillationcircuit 72 has a function of causing the resonator element 6 tooscillate and generating an oscillation signal of which temperature iscompensated based on the temperature detected by the temperature sensor71. In other words, the oscillation circuit 72 includes an oscillationcircuit unit 721 that is electrically coupled to the resonator element6, amplifies the output signal of the resonator element 6, andoscillates the resonator element 6 by feeding back the amplified signalto the resonator element 6, and a temperature compensation circuit unit722 that performs temperature compensation so that the frequencyvariation of the output signal is smaller than the frequencytemperature-characteristics of the resonator element 6 itself, based onthe temperature information output from the temperature sensor 71. Asthe oscillation circuit 72, for example, an oscillation circuit such asa Pierce oscillation circuit, an inverter type oscillation circuit, aColpitts oscillation circuit, a Hartley oscillation circuit, or the likecan be used. For example, the temperature compensation circuit unit 722included in the oscillation circuit 72 may adjust the oscillationfrequency of the oscillation circuit unit 721 by adjusting thecapacitance of a variable capacitance circuit coupled to the oscillationcircuit unit 721 or adjust the frequency of the output signal of theoscillation circuit unit 721 by a PLL circuit or a direct digitalsynthesizer circuit.

Thus, by housing both the temperature sensor 71 and the resonatorelement 6 in the inner package 5, the temperature sensor 71 can bedisposed in the same space as the resonator element 6 and in thevicinity of the resonator element 6. Therefore, the temperature sensor71 can detect the temperature of the resonator element 6 with higheraccuracy, and the temperature compensation by the oscillation circuit 72becomes more accurate.

In the embodiment, the temperature sensor 71 is formed of an ICtemperature sensor and is built in the first circuit element 7. That is,the temperature sensor 71 is integrated with the first circuit element7. As a result, the size of the temperature compensated crystaloscillator 3 can be reduced. However, the temperature sensor 71 is notlimited thereto, and for example, may be a discrete component providedseparately from the first circuit element 7. In this case, thetemperature sensor 71 can be configured by a thermistor, a thermocouple,or the like, for example.

The temperature compensated crystal oscillator 3 has been describedabove. The temperature compensated crystal oscillator 3 has the fourexternal terminals 543 described above, and as shown in FIG. 2, one is aterminal 543 a for power supply voltage supplied to the first circuitelement 7, one is a terminal 543 b for ground with respect to the powersupply voltage, one is a terminal 543 c for oscillation signal outputfrom the oscillation circuit 72, and one is a terminal 543 d fortemperature information signal output from the temperature sensor 71.

The inner package 5 includes a first side 5 a that is located on theminus side in the X-axis direction and parallel to the Y-axis, and asecond side 5 b that is located on the plus side in the X-axis directionand parallel to the Y-axis in plan view. That is, the second side 5 b isdisposed closer to the second circuit element 4 than the first side 5 a.The terminal 543 b is located at the corner located on the Y-axisdirection plus side end of the first side 5 a, the terminal 543 d islocated at the corner located on the Y-axis direction minus side end ofthe first side 5 a, the terminal 543 c is located at the corner locatedat the Y-axis direction plus side end of the second side 5 b, and theterminal 543 a is located at the corner located at the Y-axis directionminus side end of the second side 5 b. According to such an arrangement,the terminal 543 c can be disposed closer to the second circuit element4, and the wiring length between the terminal 543 c and the secondcircuit element 4 can be shortened. Therefore, it is difficult for noiseto be added to the oscillation signal output from the oscillationcircuit 72, and an accurate oscillation signal can be output to thesecond circuit element 4. However, the number, arrangement, andapplication of the external terminals 543 are not particularly limited.

As shown in FIG. 1, the temperature compensated crystal oscillator 3 isdisposed with the second lid 52 facing the bottom surface of the recessportion 211 b, and the second lid 52 is fixed to the bottom surface ofthe recess portion 211 b via an insulating bonding member B1. That is,the temperature compensated crystal oscillator 3 is disposed in the thinportion 21A of the first base substrate 21. By fixing the second lid 52to the bottom surface of the recess portion 211 b in this way, forexample, as compared with the case where the second base substrate 51 isfixed to the bottom surface of the recess portion 211 b as in a secondembodiment described later, the heat transfer path from the jointportion between the inner package 5 and the first base substrate 21 tothe resonator element 6 and the first circuit element 7 becomes longer.Therefore, the heat of the second circuit element 4 is difficult to betransmitted to the resonator element 6 and the first circuit element 7.As a result, the temperature difference between the resonator element 6and the temperature sensor 71 can be further reduced.

The insulating bonding member B1 is not particularly limited, and forexample, various resin adhesives such as epoxy, polyimide, and siliconecan be used. Such an insulating bonding member B1 has a lower thermalconductivity than a metal-based conductive bonding member typified bysolder, a metal paste, and the like, and compared with the case wherethe first base substrate 21 and the temperature compensated crystaloscillator 3 are bonded via a conductive bonding member, the heat of thefirst base substrate 21 is less likely to be transmitted to the innerpackage 5 via the insulating bonding member B1. Therefore, theheat-insulating property of the temperature compensated crystaloscillator 3 is enhanced, and the temperature compensated crystaloscillator 3 is hardly affected by the external temperature. Inaddition, the heat of the second circuit element 4 is not easilytransmitted to the temperature compensated crystal oscillator 3 throughthe first base substrate 21, thereby effectively suppressing anexcessive increase in the temperature of the resonator element 6 and thefirst circuit element 7 in the inner package 5 and an increase in thetemperature difference between the resonator element 6 and thetemperature sensor 71. As a result, the temperature sensor 71 can detectthe temperature of the resonator element 6 with higher accuracy, andaccordingly, the temperature compensation by the oscillation circuit 72becomes more accurate. Therefore, the oscillator 1 is capable ofoutputting a highly accurate frequency signal.

As shown in FIG. 2, among the four external terminals 543 included inthe temperature compensated crystal oscillator 3, the terminals 543 a,543 b, and 543 d are electrically coupled to the internal terminal 241via the bonding wires BW2, respectively. On the other hand, the terminal543 c is directly coupled to the second circuit element 4 through abonding wire BW5. Thereby, the wiring length between the terminal 543 cand the second circuit element 4 can be shortened. Therefore, it isdifficult for noise to be added to the oscillation signal output fromthe oscillation circuit 72, and an accurate oscillation signal can beoutput to the second circuit element 4. The terminal 543 a is furtherelectrically coupled to the second circuit element 4 through a bondingwire BW6. As a result, the power supply voltage can also be supplied tothe second circuit element 4.

As described above, since each external terminal 543 faces the first lid22 side by fixing the temperature compensated crystal oscillator 3 tothe first base substrate 21 with the second lid 52 facing the bottomsurface of the recess portion 211 b, connection by the bonding wiresBW1, BW2, BW5, and BW6 can be easily performed.

As shown in FIG. 1, the second circuit element 4 is accommodated in theouter package 2 and is bonded to the bottom surface of the recessportion 211 c via a bonding member B2. That is, the second circuitelement 4 is disposed in the thick portion 21B of the first basesubstrate 21. The bonding member B2 is not particularly limited, and maybe, for example, a conductive bonding member typified by a metal bump,solder, a brazing material, a metal paste, a conductive resin adhesive,or may be an insulating bonding member typified by a resin adhesive, butmay be a conductive bonding member.

Since a conductive bonding member contains a metal material, theconductive bonding member has a higher thermal conductivity than aninsulating bonding member that does not include a metal materialtypified by a resin adhesive, and the heat of the second circuit element4 is easily transferred to the outer package 2 through the bondingmember B2. Therefore, the heat of the second circuit element 4 is easilyreleased from the outer package 2 to the outside, and excessivetemperature rise of the second circuit element 4 and heat accumulationin the first internal space S2 can be suppressed. Since the heatdissipation of the second circuit element 4 is increased, the heat ofthe second circuit element 4 becomes difficult to be transmitted to theinner package 5, thereby more effectively suppressing an excessiveincrease in the temperature of the resonator element 6 and the firstcircuit element 7 as described above and an increase in the temperaturedifference between the resonator element 6 and the temperature sensor71. As a result, the temperature sensor 71 can accurately detect thetemperature of the resonator element 6, and the temperature compensationby the oscillation circuit 72 becomes more accurate. Therefore, theoscillator 1 is capable of outputting a highly accurate frequencysignal.

As shown in FIG. 5, such a second circuit element 4 includes afractional frequency division type PLL circuit 40 (phase synchronizationcircuit) as a frequency control circuit that controls the frequency ofthe oscillation signal output from the oscillation circuit 72 andfurther corrects the frequency-temperature characteristics remaining inthe oscillation signal output from the temperature compensated crystaloscillator 3, a storage unit 48 in which a temperature correction table481 is stored, and an output circuit 49. In the embodiment, the PLLcircuit 40, the storage unit 48, and the output circuit 49 areconstituted as one-chip circuit elements, but may be constituted by aplurality of chip circuit elements, or a part thereof may be constitutedby discrete components.

The PLL circuit 40 includes a phase comparator 41, a charge pump 42, alow-pass filter 43, a voltage-controlled oscillation circuit 44, and afrequency dividing circuit 45. The phase comparator 41 compares thephase difference between the oscillation signal output from theoscillation circuit 72 and the clock signal output from the frequencydividing circuit 45 and outputs the comparison result as a pulsevoltage. The charge pump 42 converts the pulse voltage output from thephase comparator 41 into a current, and the low-pass filter 43 smoothensand converts the current output from the charge pump 42.

The voltage-controlled oscillation circuit 44 outputs a signal of whichfrequency changes according to a control voltage using the outputvoltage of the low-pass filter 43 as the control voltage. Thevoltage-controlled oscillation circuit 44 of the embodiment is an LCoscillation circuit configured by using an inductance element such as acoil and a capacitance element such as a capacitor, but is not limitedthereto, and for example, an oscillation circuit using a piezoelectricresonator such as a crystal resonator can be used. The frequencydividing circuit 45 outputs a clock signal obtained by dividing theclock signal output from the voltage-controlled oscillation circuit 44by a fraction by a frequency dividing ratio determined from thetemperature information signal output from the temperature sensor 71 andthe temperature correction table 481. The frequency dividing ratio ofthe frequency dividing circuit 45 is not limited to the configurationdetermined by the temperature correction table 481. For example, thefrequency dividing ratio may be determined by a polynomial operation, ormay be determined by a neural network operation based on a machinelearning model.

The output circuit 49 receives the clock signal output from the PLLcircuit 40 and generates an oscillation signal of which amplitude isadjusted to a desired level. The oscillation signal generated by theoutput circuit 49 is output to the outside of the oscillator 1 via theexternal terminal 243 of the oscillator 1.

As described above, the frequency-temperature characteristics remainingin the oscillation signal output from the temperature compensatedcrystal oscillator 3 is further corrected by the PLL circuit 40, wherebythe oscillator 1 having a smaller frequency deviation due to temperaturecan be obtained. The PLL circuit 40 is not particularly limited. Forexample, an integer frequency division type PLL circuit that divides theoscillation signal output from the oscillation circuit 72 by an integerfrequency-division ratio may be provided between the oscillation circuit72 and the phase comparator 41. Further, the PLL circuit 40 is notlimited to the circuit that further compensates the temperature of theoutput signal of the temperature compensated crystal oscillator 3. Forexample, the PLL circuit 40 may be configured to multiply the outputfrequency of the temperature compensated crystal oscillator 3 by a fixedvalue in order to obtain a desired frequency signal.

The second circuit element 4 configured as described above is arrangedside by side with the temperature compensated crystal oscillator 3 inthe X-axis direction in plan view. The second circuit element 4 is notin contact with the temperature compensated crystal oscillator 3.Therefore, it is difficult for the heat of the second circuit element 4to be transmitted to the temperature compensated crystal oscillator 3,and the temperature difference between the resonator element 6 and thetemperature sensor 71 due to the heat of the second circuit element 4 iseffectively suppressed. Accordingly, the temperature sensor 71 candetect the temperature of the resonator element 6 with higher accuracy.In particular, in the embodiment, the second circuit element 4 includesthe PLL circuit 40, and the PLL circuit 40 has a relatively large powerconsumption and easily generates heat. Therefore, by arranging thetemperature compensated crystal oscillator 3 and the second circuitelement 4 side by side in plan view, the above-described effects can beexhibited more remarkably. Since the second circuit element 4 alsooperates based on the temperature information signal output from thetemperature sensor 71, the second circuit element 4 is less susceptibleto the own heat generation thereof compared to the case where thetemperature sensor 71 is provided in the second circuit element 4. Thedirection in which the temperature compensated crystal oscillator 3 andthe second circuit element 4 are arranged in plan view is not limited tothe X-axis direction, and may be, for example, the Y-axis direction or adirection inclined by a predetermined angle with respect to the X axis.

In the embodiment, as described above, the thin portion 21A and thethick portion 21B of which upper surfaces are displaced in the Z-axisdirection are formed on the first base substrate 21, the temperaturecompensated crystal oscillator 3 is disposed on the upper surface of thethin portion 21A, and the second circuit element 4 is disposed on theupper surface of the thick portion 21B. As a result, for example,compared with the case where the temperature compensated crystaloscillator 3 and the second circuit element 4 are arranged on the sameplane, the heat transfer path between the second circuit element 4 andthe temperature compensated crystal oscillator 3 via the first basesubstrate 21 can be lengthened, and the heat of the second circuitelement 4 is difficult to be transmitted by the temperature compensatedcrystal oscillator 3. Therefore, it is possible to more effectivelysuppress a temperature difference between the resonator element 6 andthe temperature sensor 71 due to the heat of the second circuit element4, and the temperature of the resonator element 6 can be detected withhigher accuracy by the temperature sensor 71.

In the embodiment, since a thickness t3 of the temperature compensatedcrystal oscillator 3 is larger than a thickness t4 of the second circuitelement 4, the temperature compensated crystal oscillator 3 is disposedin the thin portion 21A, and the second circuit element 4 is disposed inthe thick portion 21B. Thereby, compared with the case where arrangementis reverse, the height of the outer package 2 can be reduced. Therefore,the oscillator 1 becomes smaller.

However, the embodiment is not limited thereto. For example, the recessportion 211 c may be omitted from the first base substrate 21, and thetemperature compensated crystal oscillator 3 and the second circuitelement 4 may be disposed on the bottom surface of the recess portion211 b. For example, contrary to the embodiment, the second circuitelement 4 may be disposed in the thin portion 21A, and the temperaturecompensated crystal oscillator 3 may be disposed in the thick portion21B.

As shown in FIG. 2, when a virtual center line α that bisects the outerpackage 2 in the X-axis direction is set, the second circuit element 4overlaps the virtual center line α in plan view.

As shown in FIG. 2, the discrete components 81 and 82 are accommodatedin the outer package 2 and are disposed on the bottom surface of therecess portion 211 b. The discrete components 81 and 82 are arrangedside by side with the temperature compensated crystal oscillator 3 inthe Y-axis direction in plan view. One discrete component 81 is a firstbypass capacitor 810, and the other discrete component 82 is a secondbypass capacitor 820.

As shown in FIG. 5, the first bypass capacitor 810 is coupled to theterminal 543 a between the external terminal 243 provided in the outerpackage 2 and the power supply voltage terminal 543 a provided in theinner package 5. Thereby, noise can be removed from the power supplyvoltage supplied via the external terminal 243, and a stable powersupply voltage can be supplied to the first circuit element 7.

On the other hand, the second bypass capacitor 820 is coupled to theterminal 543 d between the terminal 543 d for the output signal of thetemperature sensor 71 and the PLL circuit 40. Thereby, noise can beremoved from the temperature information signal output from thetemperature sensor 71, and a more accurate temperature informationsignal can be supplied to the PLL circuit 40. Therefore, the frequencydivision ratio by the frequency dividing circuit 45 can be determinedwith higher accuracy.

As shown in FIG. 2, the first bypass capacitor 810 and the second bypasscapacitor 820 are arranged side by side in the X-axis direction, and anend portion 811 on the plus side in the X-axis direction of the firstbypass capacitor 810 and an end portion 821 on the minus side in theX-axis direction of the second bypass capacitor 820 face each other. Theend portion 811 of the first bypass capacitor 810 and the end portion821 of the second bypass capacitor 820 are both coupled to the ground.That is, the end portions 811 and 821 on facing sides of the first andsecond bypass capacitors 810 and 820 have the same potential. Thereby, ashort circuit between the end portions 811 and 821 is suppressed, and ahighly reliable circuit can be configured. Further, the first and secondbypass capacitors 810 and 820 can be disposed closer to each other, andthe size of the oscillator 1 can be reduced. However, the arrangement ofthe first and second bypass capacitors 810 and 820 is not particularlylimited. For example, the end portions 811 and 821 facing each other mayhave different potentials.

The discrete components 81 and 82 are not limited to the first andsecond bypass capacitors 810 and 820, and may be a thermistor, aresistor, a diode, or the like, for example. At least one of thediscrete components 81 and 82 may be omitted, or another component maybe added.

The oscillator 1 has been described above. As described above, theoscillator 1 includes the outer package 2 as a first container havingthe first internal space S2 including the first base substrate 21 andthe first lid 22 bonded to the first base substrate 21, the innerpackage 5 as a second container having the second internal space S5fixed to the first base substrate 21 in the first internal space S2 andhaving the second base substrate 51 and the second lid 52 bonded to thelower surface (one main surface) of the second base substrate 51, theresonator element 6 disposed on the lower surface side of the secondbase substrate 51 in the second internal space S5, the temperaturesensor 71 disposed on the upper surface (the other main surface) side ofthe second base substrate 51, the first circuit element 7 having theoscillation circuit 72 disposed on the upper surface of the second basesubstrate 51 and oscillating the resonator element 6 to generate anoscillation signal based on a temperature detected by the temperaturesensor 71, and the second circuit element 4 having the PLL circuit 40 asa frequency control circuit fixed to the first base substrate 21 in thefirst internal space S2 and controls a frequency of the oscillationsignal. The inner package 5 and the second circuit element 4 arearranged side by side in plan view.

According to such a configuration, since the temperature sensor 71 andthe resonator element 6 are both disposed on the second base substrate51, the temperature sensor 71 and the resonator element 6 are easilythermally coupled via the second base substrate 51. The inner package 5and the second circuit element 4 can be arranged apart from each otherby being arranged side by side in plan view, heat exchange between theinner package 5 and the second circuit element 4 is suppressed, and thetemperature sensor 71 and the resonator element 6 can be suppressed frombeing heated unevenly by the heat of the second circuit element 4.Therefore, it is possible to effectively suppress a temperaturedifference between the resonator element 6 and the temperature sensor 71or a fluctuation in the temperature difference. As a result, thetemperature sensor 71 can detect the temperature of the resonatorelement 6 with higher accuracy, and the temperature compensation by theoscillation circuit 72 becomes more accurate. An oscillation signal witha small frequency deviation can be output from the PLL circuit 40.Therefore, the oscillator 1 is capable of outputting a highly accuratefrequency signal. Since the inner package 5 and the second circuitelement 4 do not overlap in the Z-axis direction, the outer package 2can be reduced in height.

As described above, the second base substrate 51 includes the firstrecess portion 511 that opens on the lower surface and the second recessportion 512 that opens on the upper surface. The resonator element 6 isdisposed at the bottom of the first recess portion 511, and the firstcircuit element 7 is disposed at the bottom of the second recess portion512. As a result, since the resonator element 6 and the first circuitelement 7 are disposed with the plate-like portion 513 sandwichedbetween the first recess portion 511 and the second recess portion 512of the second base substrate 51 interposed therebetween, the resonatorelement 6 and the first circuit element 7 are easily thermally coupledvia the portion 513. Therefore, the temperature difference between theresonator element 6 and the temperature sensor 71 in the first circuitelement 7 becomes smaller. As a result, the temperature sensor 71 canaccurately detect the temperature of the resonator element 6. Theresonator element 6 can be protected from the surroundings by the firstrecess portion 511, and the first circuit element 7 can be protectedfrom the surroundings by the second recess portion 512.

As described above, the temperature sensor 71 is integrated with thefirst circuit element 7. Thereby, the size of the oscillator 1 can bereduced.

As described above, the first base substrate 21 includes a thin portion21A that is a first portion and a thick portion 21B that is a secondportion that is thicker than the thin portion 21A. The inner package 5is fixed to one of the thin portion 21A and the thick portion 21B, andthe second circuit element 4 is fixed to the other. As a result, theheat transfer path between the second circuit element 4 and thetemperature compensated crystal oscillator 3 via the first basesubstrate 21 can be lengthened, and the heat of the second circuitelement 4 is difficult to be transmitted by the temperature compensatedcrystal oscillator 3. Therefore, it is possible to more effectivelysuppress a temperature difference between the resonator element 6 andthe temperature sensor 71 due to the heat of the second circuit element4, and the temperature of the resonator element 6 can be detected withhigher accuracy by the temperature sensor 71.

In particular, in the embodiment, among the inner package 5 and thesecond circuit element 4, the thin second circuit element 4 is fixed tothe thick portion 21B, and the thick inner package 5 is fixed to thethin portion 21A. Thereby, compared with the case where arrangement isreverse, the height of the outer package 2 can be reduced. Therefore,the oscillator 1 becomes smaller.

As described above, the inner package 5 includes the terminal 543 d as atemperature output terminal from which an output signal of thetemperature sensor 71 is output. The terminal 543 d is electricallycoupled to the PLL circuit 40. Thereby, the temperature informationdetected by the temperature sensor 71 can be fed back to the PLL circuit40, and a more accurate frequency signal can be output from the PLLcircuit 40.

As described above, the inner package 5 includes the terminal 543 a as apower supply terminal to which a power supply voltage for theoscillation circuit 72 is applied. The oscillator 1 includes the firstbypass capacitor 810 accommodated in the outer package 2 and coupled tothe terminal 543 a. Thereby, noise can be removed by the first bypasscapacitor 810, and a stable power supply voltage can be supplied to theoscillation circuit 72.

As described above, the oscillator 1 includes the first bypass capacitor810 and the second bypass capacitor 820 that are accommodated in theouter package 2 and fixed to the first base substrate 21. One end of thefirst bypass capacitor 810 and one end of the second bypass capacitor820 are disposed to face each other, and the end portions 811 and 821 onfacing sides of the first bypass capacitor 810 and the second bypasscapacitor 820 have the same potential. Thereby, a short circuit betweenthe end portions 811 and 821 can be suppressed, and the first and secondbypass capacitors 810 and 820 can be disposed closer to each other.Therefore, the size of the oscillator 1 can be reduced.

Further, as described above, the inner package 5 is fixed to the firstbase substrate 21 via the insulating bonding member B1. The insulatingbonding member B1 has a lower thermal conductivity than a metal-basedconductive bonding member typified by solder, a metal paste, and thelike, and compared with the case where the first base substrate 21 andthe temperature compensated crystal oscillator 3 are bonded via aconductive bonding member, the heat of the first base substrate 21 isless likely to be transmitted to the inner package 5 via the insulatingbonding member B1. Therefore, the heat-insulating property of thetemperature compensated crystal oscillator 3 is enhanced, and thetemperature compensated crystal oscillator 3 is hardly affected by theexternal temperature. In addition, the heat of the second circuitelement 4 is not easily transmitted to the temperature compensatedcrystal oscillator 3 through the first base substrate 21, therebyeffectively suppressing an excessive increase in the temperature of theresonator element 6 and the first circuit element 7 in the inner package5 and an increase in the temperature difference between the resonatorelement 6 and the temperature sensor 71. As a result, the temperaturesensor 71 can detect the temperature of the resonator element 6 withhigher accuracy, and accordingly, the temperature compensation by theoscillation circuit 72 becomes more accurate. Therefore, the oscillator1 is capable of outputting a highly accurate frequency signal.

As described above, the inner package 5 includes the first side 5 a andthe second side 5 b closer to the second circuit element 4 than thefirst side 5 a in plan view, and the terminal 543 c as an oscillationoutput terminal from which an oscillation signal from the oscillationcircuit 72 is output. The terminal 543 c is provided at one of twocorners located at both ends of the second side 5 b, in the embodiment,at a corner located on the Y-axis direction plus side. According to suchan arrangement, the terminal 543 c can be disposed closer to the secondcircuit element 4, and the wiring length between the terminal 543 c andthe second circuit element 4 can be shortened. Therefore, it isdifficult for noise to be added to the oscillation signal, and anaccurate oscillation signal can be output to the second circuit element4.

As described above, in the inner package 5, the second lid 52 is fixedto the first base substrate 21. By fixing the second lid 52 to thebottom surface of the recess portion 211 b in this way, for example, ascompared with the case where the second base substrate 51 is fixed tothe bottom surface of the recess portion 211 b as in a second embodimentdescribed later, the heat transfer path from the joint portion betweenthe inner package 5 and the first base substrate 21 to the resonatorelement 6 and the first circuit element 7 can be longer. Therefore, theheat of the second circuit element 4 is difficult to be transmitted tothe resonator element 6 and the first circuit element 7. As a result,the temperature difference between the resonator element 6 and thetemperature sensor 71 can be further reduced.

Second Embodiment

FIG. 6 is a cross-sectional view showing an oscillator according to asecond embodiment.

The embodiment is the same as the first embodiment described aboveexcept that the temperature compensated crystal oscillator 3 has adifferent posture. In the following description, the embodiment will bedescribed with a focus on differences from the above-describedembodiment, and the description of the same matters will be omitted. InFIG. 6, the same reference numerals are given to the same configurationsas those in the above-described embodiment.

As shown in FIG. 6, in the oscillator 1 of the embodiment, a pluralityof internal terminals 241 are disposed on the bottom surface of therecess portion 211 a, and a plurality of internal terminals 242 aredisposed on the bottom surface of the recess portion 211 b. The internalterminals 241 and 242 and the external terminal 243 are electricallycoupled via a wiring (not shown) formed in the first base substrate 21.

The temperature compensated crystal oscillator 3 is accommodated in thefirst internal space S2 in a posture opposite to the above-describedfirst embodiment, that is, in a posture in which the second basesubstrate 51 faces the bottom surface side of the recess portion 211 b.The second base substrate 51 is bonded to the bottom surface of therecess portion 211 b via the conductive bonding member B4 made of ametal bump such as a solder bump, and each external terminal 543 iselectrically coupled to the internal terminal 242. The temperaturecompensated crystal oscillator 3 can be mounted on the first basesubstrate 21 by, for example, flip chip mounting. According to such aconfiguration, since no bonding wire is used for the electricalconnection between the temperature compensated crystal oscillator 3 andthe first base substrate 21, it is not necessary to secure the loopheight of the bonding wire, and accordingly, the height of the outerpackage 2 can be reduced as compared with the first embodiment describedabove.

According to the second embodiment, the same effects as those of thefirst embodiment described above can be exhibited.

Third Embodiment

FIG. 7 is a perspective view showing a personal computer according to athird embodiment.

A personal computer 1100 as an electronic device shown in FIG. 7includes a main body 1104 provided with a keyboard 1102 and a displayunit 1106 provided with a display unit 1108, and the display unit 1106is supported so as to be rotatable with respect to the main body 1104via a hinge structure. Such a personal computer 1100 has a built-inoscillator 1. The personal computer 1100 includes a signal processingcircuit 1110 that performs arithmetic processing related to control ofthe keyboard 1102, the display unit 1108, and the like. The signalprocessing circuit 1110 operates based on the oscillation signal outputfrom the oscillator 1.

As described above, the personal computer 1100 as the electronic deviceincludes the oscillator 1 and the signal processing circuit 1110 thatperforms signal processing based on the output signal (oscillationsignal) of the oscillator 1. Therefore, the effect of the oscillator 1described above can be enjoyed and high reliability can be exhibited.

In addition to the personal computer 1100 described above, an electronicdevice including the oscillator 1 may be, for example, digital stillcameras, smartphones, tablet terminals, timepieces including asmartwatch, ink jet ejection apparatuses, such as an ink jet printer,wearable terminals such as a head mounted display (HMD), TVs, videocameras, video tape recorders, car navigation apparatuses, pagers,electronic notebooks, electronic dictionaries, calculators, electronicgame machines, word processors, workstations, video phones, TV monitorsfor crime prevention, electronic binoculars, POS terminals, medicalequipment such as an electronic thermometer, a blood pressure monitor, ablood glucose meter, an electrocardiogram measuring apparatus, anultrasonic diagnostic apparatus, and an electronic endoscope, fishdetectors, measuring instruments, instruments such as vehicles,aircraft, ships, base stations for mobile terminals, flight simulators,and the like.

Fourth Embodiment

FIG. 8 is a perspective view showing an automobile according to a fourthembodiment.

As shown in FIG. 8, an automobile 1500 as a vehicle includes anoscillator 1 and a signal processing circuit 1510 that operates based onan oscillation signal output from the oscillator 1. The oscillator 1 andthe signal processing circuit 1510 may be widely applied to, forexample, keyless entries, immobilizers, car navigation systems, car airconditioners, anti-lock brake systems (ABS), air bags, tire pressuremonitoring systems (TPMS), engine controls, battery monitors for hybridcars and electric cars, and electronic control units (ECU) such as avehicle body attitude control system.

Thus, the automobile 1500 as a vehicle includes the oscillator 1 and thesignal processing circuit 1510 that performs signal processing based onthe output signal (oscillation signal) of the oscillator 1. Therefore,the effect of the oscillator 1 described above can be enjoyed and highreliability can be exhibited.

The vehicle including the oscillator 1 may be, for example, a robot, adrone, a two-wheeled vehicle, an aircraft, a ship, a train, a rocket, aspacecraft, or the like in addition to the automobile 1500.

The oscillator, the electronic device, and the vehicle according to thedisclosure have been described based on the illustrated embodiments, butthe disclosure is not limited thereto, and the configuration of eachportion may be replaced with an arbitrary configuration having the samefunction. Other optional components may be added to the disclosure. Eachembodiment above-described may be combined as appropriate.

What is claimed is:
 1. An oscillator comprising: a first container thatincludes a first base substrate and a first lid bonded to the first basesubstrate and that has a first internal space; a second container thatis fixed to the first base substrate in the first internal space andthat includes a second base substrate and a second lid bonded to onemain surface of the second base substrate and has a second internalspace; a resonator element that is disposed on the one main surface ofthe second base substrate in the second internal space; a temperaturesensor that is disposed on the other main surface of the second basesubstrate; a first circuit element that is disposed on the other mainsurface of the second base substrate and that includes an oscillationcircuit oscillating the resonator element and generating an oscillationsignal on which temperature compensation is performed based on adetected temperature of the temperature sensor; and a second circuitelement that is fixed to the first base substrate in the first internalspace and that includes a frequency control circuit that controls afrequency of the oscillation signal, wherein the second container andthe second circuit element are arranged side by side in plan view, andwherein the first base substrate includes a first portion and a secondportion thicker than the first portion, the second container is fixed toone of the first portion and the second portion, and the second circuitelement is fixed to the other thereof.
 2. The oscillator according toclaim 1, wherein the second base substrate includes a first recessportion that opens on the one main surface and a second recess portionthat opens on the other main surface, the resonator element is disposedat a bottom of the first recess portion, and the first circuit elementis disposed at a bottom of the second recess portion.
 3. The oscillatoraccording to claim 1, wherein the temperature sensor is integrated withthe first circuit element.
 4. The oscillator according to claim 1,wherein a thinner one of the second container and the second circuitelement is fixed to the second portion, and a thicker one is fixed tothe first portion.
 5. The oscillator according to claim 1, wherein thesecond container includes a temperature output terminal from which anoutput signal of the temperature sensor is output, and the temperatureoutput terminal is electrically coupled to the frequency controlcircuit.
 6. The oscillator according to claim 1, wherein the secondcontainer includes a power supply terminal to which a power supplyvoltage supplied to the oscillation circuit is applied, and theoscillator further comprises a bypass capacitor that is accommodated inthe first container, and is coupled to the power supply terminal.
 7. Anoscillator comprising: a first container that includes a first basesubstrate and a first lid bonded to the first base substrate and thathas a first internal space; a second container that is fixed to thefirst base substrate in the first internal space and that includes asecond base substrate and a second lid bonded to one main surface of thesecond base substrate and has a second internal space; a resonatorelement that is disposed on the one main surface of the second basesubstrate in the second internal space; a temperature sensor that isdisposed on the other main surface of the second base sub state; a firstcircuit element that is disposed on the other main surface of the secondbase substrate and that includes an oscillation circuit oscillating theresonator element and generating an oscillation signal on whichtemperature compensation is performed based on a detected temperature ofthe temperature sensor; a second circuit element that is fixed to thefirst base substrate in the first internal space and that includes afrequency control circuit that controls a frequency of the oscillationsignal; and a first bypass capacitor and a second bypass capacitor thatare accommodated in the first container and are fixed to the first basesubstrate, wherein the second container and the second circuit elementare arranged side by side in plan view, one end of the first bypasscapacitor and one end of the second bypass capacitor are disposed toface each other, and end portions on facing sides of the first bypasscapacitor and the second bypass capacitor have the same potential. 8.The oscillator according to claim 1, wherein the second container isfixed to the first base substrate via an insulating bonding member. 9.The oscillator according to claim 1, wherein the second containerincludes a first side and a second side closer to the second circuitelement than the first side in plan view, and an oscillation outputterminal from which the oscillation signal is output, and theoscillation output terminal is provided at one of two corners located atboth ends of the second side.
 10. The oscillator according to claim 1,wherein the second lid of the second container is fixed to the firstbase substrate.
 11. An electronic device comprising: the oscillatoraccording to claim 1; and a signal processing circuit that performssignal processing based on an output signal of the oscillator.
 12. Avehicle comprising: the oscillator according to claim 1; and a signalprocessing circuit that performs signal processing based on an outputsignal of the oscillator.